July 16, 1965: Mont Blanc Tunnel Opens

1965: After 19 years of planning and construction, the Mont Blanc Tunnel officially opens. The new tunnel stretches 7 miles, linking the French town of Chamonix and the Italian town of Courmayeur. Buried 1.5 miles under the Alps’ highest peak, it becomes the world’s deepest road tunnel beneath rock and gains infamy after a deadly 1999 fire.

Until the opening of the tunnel, road traffic in the Alps between France and Italy wended its way over hairpin turns and sharp grades, with mountain passes closed the majority of the year because of snow. Italian construction teams began drilling a tunnel into Mont Blanc (or Monte Bianco on their side) to build a year-round route in 1946. The next year, France and Italy signed an agreement to build the tunnel together.

Construction, however, did not begin in earnest until May 30, 1959, with the help of an 82-ton tunnel-boring machine. Tunneling began at 4,091 feet on the French side and at 4,530 feet on the Italian side.

It took 783 tons of explosives to complete the drilling. The French and Italian teams met Aug. 4, 1962, with a discrepancy of only 5.12 inches between the two sides.

When it opened in a ceremony featuring Presidents Charles De Gaulle of France and Giuseppe Saragat of Italy, the Mont Blanc Tunnel became the world’s longest highway tunnel, more than three times longer than the previous recordholder, Liverpool’s Mersey Tunnel.

The tunnel operated without a major incident for 34 years, with management of the roadway divided between the French ATMB (Autoroutes et Tunnels du Mont-Blanc) and Italian SITMB (Società Italiana per azioni per il Traforo del Monte Bianco). In 1990, the agencies installed fireproof shelters and advanced video-surveillance cameras in the tunnel, and upgraded existing safety equipment.

At 10:46 a.m. on March 24, 1999, a refrigerated Volvo FH12 tractor trailer filled with flour and margarine and piloted by Belgian truck driver Gilbert Degraves entered the French side of the tunnel bound for Italy. Six minutes later, oncoming drivers began flashing their headlights at Degraves, who noticed white smoke pouring from the truck’s cab. Degraves pulled over and attempted to fight the fire, but was forced back when the truck burst into flames. Though Degraves escaped, 50 others were trapped in the tunnel with the burning truck.

Over the next 10 minutes, temperatures in the tunnel climbed to a staggering 1,800 degrees Fahrenheit. Since the V-shaped tunnel acted like a chimney, it was soon filled with toxic smoke that instantly killed all those who breathed it in. Without oxygen, vehicle engines stalled and drivers were trapped in the tunnel. Some who escaped sought refuge in the fireproof shelters built into the walls of the tunnel, but even the shelters could not withstand the heat of this fire.

With the heroic efforts of firefighting teams and Pierlucio Tinazzi — a security guard who perished in the fire after evacuating 10 survivors on his motorcycle — 12 people of the 50 trapped in the tunnel survived. It took five days for temperatures to cool down enough for engineering teams to begin removing debris.

After three years, $481 million in reconstruction and safety upgrades — and the restructuring of the separate French and Italian companies into a single management entity — the Mont Blanc Tunnel reopened to traffic March 9, 2002. A court found in 2005 that the fire could have been prevented with better management and safety precautions and sentenced 13 defendants to jail time or fines.

Today, international truck traffic has returned to the tunnel. The associated air pollution is a cause of concern for some residents of nearby communities who formed the Association pour le Respect du Site du Mont-Blanc to ban trucks from the tunnel. While pollution can become unpleasant in the valleys surrounding the tunnel entrances, there are no plans to close the tunnel to trucks any time soon.

Source: Various

Photo: Vehicles leave Italy through this entrance to the Mont Blanc Tunnel.bramhall/Flickr

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